This application relates generally to lawful intercept, and more particularly, to performing near-real-time monitoring and reporting of intercepted communications in a group call setting.
The Communications Assistance for Law Enforcement Act (CALEA) is a United States wiretapping law to aid law enforcement in its effort to conduct criminal investigations requiring wiretapping of digital telephone networks. Existing implementations of a CALEA system typically only handle one-to-one calls, and do not work for group communications such as push-to-talk (PTT) and VoIP communications. Moreover, existing implementations deliver call signaling and call media (voice content) to the Law Enforcement Authority (LEA) across different paths, which often results in receiving this content at different times, making it difficult or impossible to correlate. Further, the different network components required for delivering the call signaling and call media provide opportunities for such components to be bypassed by custom VoIP solutions, as well as providing complications and cost in scaling.
Additionally, some of the existing implementations rely of out of band signaling, like SMS, to provide location information corresponding to the call signaling and media. This out of band signaling may be detected by the end user, which is not desirable. Moreover, the use of best effort, out of band signaling (e.g., SMS) on a different physical layer than the PTT/VoIP signaling (e.g., 1× vs DoRA) does not guarantee the delivery of the out of band location information. Further, the device user may be able to shut it off the SMS or other location based service. Other implementations rely on the Network (e.g., RAN, Core Network) to extract the location information for specific application services, however, such functionality may not be universally available. Thus, existing CALEA implementations have many drawbacks.